He includes in his listings there the Raynox DCR150 and 250. He also shows some of the other Elpro lenses which can appear secondhand at reasonable prices from time to time, but the thread sizes can be tricky.

Sven also includes the Sony VCL M3358. I have one of those myself and I find it to be an excellent lens.

Thank you Ian for your kind words. Yes, Sven has done a great job with his pages, you'll find the reference and link to his work in my paper at the very beginning.

The Leitz Elpros are available in Series Vi (44mm), Series VII (54mm) and 55mm, but you can find enough of them used in 55mm (at least here in Europe), so there is no need to fiddle with exotic step adapters for smaller diameters.

You will be right about the Sony lens, I may add it as an alternative. It was not in my focus due to the 58mm size.